[The polyphosphate synthetase of Saccharomyces cerevisiae]

The polyphosphate-synthetase, isolated from a homogenate of phosphate starved cells, catalyses the synthesis of linear polyphosphates from orthophosphate. It is localized in the membrane fraction which deposits between 400 and 1000 X g; its optimal pH is 7.1; its KM toward orthophosphate is 4.0 X 10(-4) M; ATP stimulates the reaction. The enzyme synthezises especially polyphosphates with short chain length.